Tesla's Model S is the only car approaching a 300-mile range, but improving technology could change that quickly. Image owned by The Motley Fool.

From an research perspective, the drive to build high-density batteries for electric vehicles is just starting. Sure, research on better batteries has been going on for years, but until the last year or two the electric-vehicle market was so small that universities, much less large battery manufacturers, didn't see it as a priority.

That's why Tesla Motors (NASDAQ:TSLA) essentially stuffed a bunch of computer batteries into a car -- it was the best option available. A decade or two from now we may look back on the lithium ion-fueled Model S as a stepping stone to a more electrified world, one that is powered by the next generation of battery technology.

Research that could make lithium ion batteries obsolete
Scientists at the University of Waterloo in Ontario announced this week that they have made a breakthrough in lithium-sulfur battery technology that could increase an EVs range by 3 times with the same weight and a lower cost. Essentially, sulfur would be a good battery cathode material because, along with increasing energy density, it is abundant, light, and cheap. So finding materials that make the battery's construction possible would be a breakthrough.  

Lithium-sulfur technology is far from production, but if it lives up to expectations we could see a Model S with a range of nearly 900 miles or a Nissan Leaf that could go 250 miles on a single charge, without a bigger battery.

More technologies that could advance EVs
Lithium-sulfer is not the only technology being tested to improve battery performance. Dozens of research institutes and large companies are beginning to work on batteries given the large market potential. Here are a few technologies that have shown promise in the laboratory.

  • Metal-air cells could hypothetically increase the energy density of an EV battery while also lowering costs.  
  • Flow batteries are essentially rechargeable fuel cells that have shown promise. So far, though, they have proven to be too complex for mass production and have a lower energy density than lithium-ion batteries today.  
  • Lithium-air is a technology IBM (NYSE:IBM) is working on in an effort to provide electric vehicles with a 500-mile range. Even if successful the company doesn't expect to see commercial applications before 2020.  
  • Lithium silicon polymer is a concept the Lawrence Berkeley National Laboratory has been developing to improve energy density in lithium-based cells by adding a specially designed polymer to the cell's anode.  

If even just one of these technologies, or other corresponding battery efforts, succeeds, it could be a windfall for the company that can successfully commercialize that big advancement in battery technology.

The most important question for EV makers to answer
Electric vehicles have made huge advancements over the last five years, but they still need better batteries to go mainstream. A 50-mile range is enough to attract die-hard EV enthusiasts, but a 500-mile range would appeal to nearly everyone. 

If researchers can figure out a way to pack 500 miles worth of energy into an electric vehicle, and to ensure it could be charged overnight, the industry's growth could explode.

The missing link is the technology that makes a longer-range vehicle possible. Given the capital flowing into research and development, I think it's only a matter of time before batteries take a major step forward. And I, for one, hope one (or more) of these technologies make a future filled with electric vehicles possible.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.